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The act holds the record for sparking the longest filibuster in the history of the U.S. Senate

This story was originally published April 10.

(CNN)The Civil Rights Act of 1964 -- hailed by some as the most important legislation in American history -- was signed into law 50 years ago Wednesday.

It was known as the "bill of the century." But many Americans today probably couldn't say exactly what the legislation accomplished.

"It's really the law that created modern America," said Todd S. Purdum, author of "An Idea Whose Time Has Come." "Its goal was to help finish the work of the Civil War, 100 years after the war had ended, and to make the promise of legal equality for blacks and whites, even though actual equality is elusive to this day."

The law revolutionized a country where blacks and whites could not eat together in public restaurants under Jim Crow laws, or stay at the same hotel. It outlawed discrimination in public places and facilities and banned discrimination based on race, gender, religion or national origin by employers and government agencies. It also encouraged the desegregation of public schools.

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"This did all of those things. It changed everything about ordinary life for black Americans all over the country," Purdum said. "I think when you try to explain to people today -- I have children 10 and 14 years old, and I don't think they can really imagine a world like (this) existed before this law."

The act had the longest filibuster in U.S. Senate history, and after a bloody, long civil rights struggle, the Senate passed the act 73-27 in July 1964. It became law less than a year after President John F. Kennedy's assassination.

Here are a few surprising facts about how the Civil Rights Act of 1964 became law:

1. More Republicans voted in favor of the Civil Rights Act than Democrats

In the 1960s, Congress was divided on civil rights issues -- but not necessarily along party lines.

The civil rights movement in photos 20 photos

The civil rights movement in photos20 photos

The civil rights movement in photos – President Lyndon B. Johnson shakes hands with civil rights leader Martin Luther King Jr. after signing the Civil Rights Act of 1964. The LBJ Presidential Library is hosting a Civil Rights Summit this week to mark the 50th anniversary of the legislation.

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The civil rights movement in photos20 photos

The civil rights movement in photos – Jackie Robinson, who broke Major League Baseball's color barrier, poses in the dugout with some of his Brooklyn Dodgers teammates during his first game on April 15, 1947.

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The civil rights movement in photos20 photos

The civil rights movement in photos – Rosa Parks poses for her booking photo after she was arrested in Montgomery, Alabama, for refusing to give up her bus seat to a white passenger in 1955.

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The civil rights movement in photos20 photos

The civil rights movement in photos – Students of Central High School in Little Rock, Arkansas, shout insults at Elizabeth Eckford as she walks toward the school building on the first day of school in 1957. Schools in Arkansas integrated races after the Supreme Court ruling in Brown v. Board of Education.

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The civil rights movement in photos20 photos

The civil rights movement in photos – As part of his training for sit-in protests in 1960, student Virginius Thornton practices not reacting to smoke being blown in his face.

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The civil rights movement in photos20 photos

The civil rights movement in photos – Freedom Riders sit on a bus during a trip from Montgomery to Jackson, Mississippi, in 1961. The Freedom Riders would brave mobs and endure savage beatings to desegregate interstate travel.

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The civil rights movement in photos20 photos

The civil rights movement in photos – A black woman and a white woman sit next to each other at a New York City restaurant in 1962.

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The civil rights movement in photos20 photos

The civil rights movement in photos – A police dog jumps at a 17-year-old civil rights demonstrator in Birmingham, Alabama, on May 3, 1963. The image appeared on the front page of The New York Times the next day.

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The civil rights movement in photos20 photos

The civil rights movement in photos – Firefighters turn their hoses on demonstrators in Birmingham in July 1963. When civil rights protesters stalled in Birmingham, the city's African-American children took to the streets. Their bravery facing water hoses and dogs riveted the nation.

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The civil rights movement in photos20 photos

The civil rights movement in photos – King addresses the crowd at the Lincoln Memorial in Washington, where he delivered his famous "I Have a Dream" speech on August 28, 1963.

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The civil rights movement in photos20 photos

The civil rights movement in photos – People gather on the National Mall during the March on Washington on August 28, 1963.

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The civil rights movement in photos20 photos

The civil rights movement in photos – Sarah Jean Collins, 12, lies in bed after being blinded by the dynamite that killed her sister in the bombing of a Birmingham church in September 1963. Four African-American girls were killed in the blast.

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The civil rights movement in photos20 photos

The civil rights movement in photos – The family of Carol Robertson, a 14-year-old girl killed in the church bombing, attend a graveside service for her in Birmingham on September 17, 1963.

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The civil rights movement in photos20 photos

The civil rights movement in photos – A 1964 FBI poster seeks information on the whereabouts of Andrew Goodman, James Earl Chaney and Michael Henry Schwerner. The three civil rights workers disappeared in rural Mississippi in the summer of 1964. Their bodies were found 44 days later. They had been tortured before they were murdered.

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The civil rights movement in photos20 photos

The civil rights movement in photos – Nation Of Islam leader and civil rights activist Malcolm X poses for a portrait in 1965. Malcolm was a symbol of black defiance who ridiculed King's stance on nonviolence.

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The civil rights movement in photos20 photos

The civil rights movement in photos – The car belonging to Viola Liuzzo sits off the road near Selma, Alabama, in 1965. Liuzzo, a white housewife from Detroit, felt compelled to drive to Selma to help the civil rights movement after seeing demonstrators beaten on television. While driving on a deserted road in the small town one night, Liuzzo's car was run off the road and she was shot to death. Her death showed the nation that the civil rights movement was not just an African-American struggle -- it was an American struggle.

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The civil rights movement in photos20 photos

The civil rights movement in photos – Memphis sanitation workers hold signs with the slogan "I am a man" during a strike in 1968. Their campaign against discrimination and poor conditions in the workplace brought King to Memphis.

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The civil rights movement in photos20 photos

The civil rights movement in photos – King lies bleeding at the feet of other civil rights leaders after he was shot on the balcony of the Lorraine Motel in Memphis, Tennessee, on April 4, 1968.

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The civil rights movement in photos20 photos

The civil rights movement in photos – King's widow, Coretta Scott King, and their daughter Yolanda sit in a car on their way to his funeral in Atlanta on April 9, 1968.

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The civil rights movement in photos – U.S. Olympians Tommie Smith, center, and John Carlos raise their fists in protest during the U.S. national anthem, which was being played after Smith won the 200 meters at the 1968 Summer Olympics in Mexico City.

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"Most people don't realize that today at all -- in proportional terms, a far higher percentage of Republicans voted for this bill than did Democrats, because of the way the Southerners were divided," said Purdum.

The division was geographic. The Guardian's Harry J. Enten broke down the vote, showing that more than 80% of Republicans in both houses voted in favor of the bill, compared with more than 60% of Democrats. When you account for geography, according to Enten's article, 90% of lawmakers from states that were in the Union during the Civil War supported the bill compared with less than 10% of lawmakers from states that were in the Confederacy.

Enten points out that Democrats still played a key role in getting the law passed.

"It was also Democrats who helped usher the bill through the House, Senate, and ultimately a Democratic president who signed it into law," Enten writes.

2. A fiscal conservative became an unsung hero in helping the Act pass

Ohio's Republican Rep. William McCulloch had a conservative track record -- he opposed foreign and federal education aid and supported gun rights and school prayer. His district (the same one now represented by House Speaker John Boehner) had a small African-American population. So he had little to gain politically by supporting the Civil Rights Act.

Photos: Leonard Freed's March on Washington 10 photos

Photos: Leonard Freed's March on Washington10 photos

Leonard Freed's March on Washington – August 28, 1963, was one of the most important days for the civil rights movement. Over 200,000 people gathered on the National Mall in Washington to hear Martin Luther King Jr. deliver his famous "I Have a Dream" speech from the steps of the Lincoln Memorial. Magnum photographer Leonard Freed (1929-2006) was there documenting that historic day.

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Photos: Leonard Freed's March on Washington10 photos

Leonard Freed's March on Washington – The crowd gathers at the National Mall.

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Photos: Leonard Freed's March on Washington10 photos

Leonard Freed's March on Washington – People sing together during the march.

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Photos: Leonard Freed's March on Washington10 photos

Leonard Freed's March on Washington – Though the name March on Washington"is well known, the full title of the gathering the March on Washington for Jobs and Freedom.

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Photos: Leonard Freed's March on Washington10 photos

Leonard Freed's March on Washington – People sing together during the rally.

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Photos: Leonard Freed's March on Washington10 photos

Leonard Freed's March on Washington – Ten leaders of the civil rights movement met with President John F. Kennedy, Vice President Lyndon B. Johnson, Labor Secretary W. Willard Wirtz and Burke Marshall, head of the Justice Department's Civil Rights Division, in the Cabinet room of the White House during the demonstration.

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Photos: Leonard Freed's March on Washington10 photos

Leonard Freed's March on Washington – People watch and wait for speakers.

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Photos: Leonard Freed's March on Washington10 photos

Leonard Freed's March on Washington – Though the most iconic shot from the March on Washington may be of King waving to the crowd, Freed moved throughout the crowd finding the faces that weren't seen in the papers.

Leonard Freed's March on Washington – This year marks the 50th anniversary of the historic march.

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EXPAND GALLERY

Yet he became a critical leader in getting the bill passed.

His ancestors opposed slavery even before the Civil War, and he'd made a deal with Kennedy tosee thebill through to passage.

"The Constitution doesn't say that whites alone shall have our most basic rights, but that we all shall have them," McCulloch would say to fellow legislators.

Later, he would play a key role in the 1965 Voting Rights Act and the 1968 Fair Housing Act and become part of the Kerner Commission, appointed by the Johnson administration to investigate the 1967 race riots.

Kennedy's widow, Jacqueline Kennedy, wrote him an "emotional" letter when he retired from Congress in 1972.

"You made a personal commitment to President Kennedy in October 1963, against all interests of your district," she wrote. "There were so many opportunities to sabotage the bill, without appearing to do so, but you never took them. On the contrary, you brought everyone else along with you."

3. Malcolm X and Martin Luther King Jr. met for the first and only time during Senate debate on the act

Martin Luther King Jr. and Malcolm X met briefly once as the Civil Rights Act of 1964 was being debated in Washington.

Known for his direct rhetoric in denouncing America's treatment of African-Americans, Malcolm X was a stark contrast to King, who preached tolerance and peace in achieving equal rights.

Some scholars say the two could have formed an alliance, as Malcolm X moved away from the Nation of Islam. But it never happened: Malcolm X was shot and killed less than a year after their first and only encounter. King was assassinated in 1968.

4. The act didn't help just black Americans

Women, religious minorities, Latinos and whites also benefited from the Civil Rights Act, which would later serve as a model for other anti-discrimination measures passed by Congress, including the Americans with Disabilities Act and the Pregnancy Discrimination Act.

Under the Civil Rights Act, women who had been fired because they became pregnant, or were not hired because they had small children, now had recourse. As a result of Title VII, "male only" job notices became illegal for the first time.

Smith, who was chairman of the House Rules Committee, came up with many tactics to discourage the passage of the bill's Title VII, which would outlaw employment discrimination because of race, color, religion or national origin.

6. The 1964 law didn't do much to address discrimination at the ballot box

Black men were granted the right to vote in 1870 under the 15th Amendment (women followed 50 years later). Yet many obstacles -- including literacy tests and poll taxes -- prevented most blacks in the South from casting ballots.

Just a few months before the Voting Rights Act, the 24th Amendment to the U.S. Constitution was ratified to remove poll taxes as a condition for voting in federal elections. All the 1964 Civil Rights Act did was to mandate the same voting rules nationwide.

It wasn't until the following year that the 1965 Voting Rights Act would suspend the use of literacy tests.